The phrase "a minimal part" is correct and usable in written English.
It can be used to describe a small or insignificant portion of something, often in contexts discussing components or contributions.
Example: "In the overall project, my contribution was just a minimal part of the entire effort."
Alternatives: "a small portion" or "a minor component".
"We will continue to care for refugees, but they make up a minimal part of the human wave.
Few were more successful at this assimilation game than China — and more adamant in insisting that the outside world really played a minimal part in the metamorphosis of its world perception and the impact it had on its art.
MANHATTAN: WOMAN MINIMIZES ROLE IN DEATH -- A woman who was convicted with a friend in the 1997 slaying of a man in Central Park testified in a deposition this week that she had played only a minimal part in the crime.
Besides, she points out, the CV is only a minimal part of a job application.
Just a minimal part of them, 6%, consists of high speed lines, connecting 11 biggest Italian cities.2 On the opposite, most of them, are conventional lines divided in fundamentally lines, above 6000 km, complementary lines, above 9000 km and nodes lines, that are located around metropolitan areas, above 950 km.
In any case, food legumes occupy a minimal part of arable land, mostly dominated by cereal crops [99]; soybean represents the most important and cultivated legume, acreage of which reached 117.72 million ha in 2014 (steadily increased over years, see also Table 3), which is about that of the other grain legumes, but still far below the major cereals (e.g. rice, wheat, maize).
Some of Mr. Gore's advisers would prefer that Mr. Clinton play a relatively minimal part in the postconvention campaign, similar to President Reagan's role in George Bush's 1988 campaign.
What about the set of all minimal parts of clay, i.e., the set of all the instances of clay that have no other instance of clay as part?
Once the numerical modelling of the part was done, improvement of the production process was performed based upon the desired objective function, i.e., a uniform part thickness distribution and/or minimal part weight.
In fact, this notion does not apply in this case, since a mass noun like wine has no linguistically specified minimal part.
